The invention relates to an electronic timer. The electronic timer is provided with a data memory for storing timer data inputted through an external designation operation. For storing the timer data into the data memory, the timer data must be arranged in a correct way. For example, for the timer of the 12-hour operating type, time must be expressed in terms of clock data within a range from 1:00 to 12:59 and with designation of A.M. or P.M. The time expression further needs a designation of the control data to control items to be controlled, such as ON and OFF data for timer switching. Unless the timer data given is arranged properly, it is necessary to inhibit such data from being inputted into the data memory of the timer. It is known that there is, for example, an electronic timer which inhibits the timer data from entering if it is the incorrect or improper arrangement.
The electronic timer, however, has no means to tell an operator as to whether the timer data has been loaded into the memory or not.
There may be a problem that when an operator designates the timer data erroneously he is apt to think that the timer data has already been set in the data storage in spite of the fact that it is not stored actually.
There is proposed an electronic timer able to judge whether the timer data is proper or not in the arrangement. In the timer, when the timer data is properly set in the data memory, a display in the display section is switched. When it is improperly set, the display is left unchanged. In this way, the timer tells an operator about a state of the setting of the timer data accurately. In using the timer, when the timer data is incorrectly set, the timer cannot indicate what portion of the timer data is improper, with a mere indication of the unchanged display. Particularly in recent data, a timer device has been developed and practically used, in which the time data of each week may be set. The timer data used in the timer of the type includes further data to designate days of the week. The above disadvantage that it is impossible to indicate the improper portion of the timer data, is seriously problematic particularly in the use of the timer device using the week timer data, in the light of the handling of the timer set.
In another conventional timer device of this type, as described in "TM1121 Universal Timer Data Manual" published by Texas Instruments Asia Limited, on September in 1977, for example, when the timer data takes the form of clock data, A.M. or P.M. also is used with relation to the clock data. On the other hand, when it is used as the time interval data, A.M. or P.M. is not used. Further in the former case, through one key transfer operation, the timer data is stored into the data memory as it stands. In the latter case, through one-time operation of the transfer key, the time data of the timer data is added to the clock data in the clock counter to be converted into the clock data, and then it is stored in the data memory.
TMS1121 Universal Timer has the following disadvantages, however. For example, in setting the timer data in the data memory in the form of the clock data, when the operator fails to designate A.M. or P.M. and under this condition, he operates the transfer key, erroneous timer data are stored in the data memory. In this case, the erroneous data stored must be erased. The erasing operation makes the operation of the timer troublesome. Generally, TV programs and FM programs are prepared for each week. When the timer operation of the timer device is set in concert with such programs, the same timer operation set is repeated, as a matter of course, every week. The timer device has no problem when it is applied for recording a serial program which is performed at the same hours every week. However, when it is applied for recording a called special program specially performed in an indefinite hour on an indefinite day of the week, the timer data once set must be erased after the timer operation starts. This is also the troublesome work for the timer operation.
Moreover, when it is designed to operate the timer device continuously for a series of days of the week from Monday to Friday, for example, the day-of-week key must be depressed each time. This also makes the timer operation troublesome.